Both agricultural productive technology and administration in USA rank first-class in the world. Exclusive agricultural resource is the main factor to make the USA success, but the most important factors are dynamic organizational structure, competitive productive mode, active public policy etc.As a topical market economy country, the government also plays critical administrative role in key issue such as production surplus, food safety, production and export support etc.Rational study on USA' key agriculture policy is significant and useful for public policy-making related to agriculture, rural and peasant in China. From the theoretical aspect, comparative research is feasible and easy, but in praxis, is complex and difficulty. More attention must be paid to similarities and differences between USA and China in nature, society, economy and culture aspects.